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Question
The mechanical equivalent of heat ____________ .
Options
has the same dimension as heat
has the same dimension as work
has the same dimension as energy
is dimensionless
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Solution
is dimensionless
If the mechanical work done (W) produces the same temperature change as heat (H),then the mechanical equivalent of heat (J) is equal to W/H. Thus,
J = W/H
Since the unit of work and heat is the same, mechanical equivalent of heat is dimensionless.
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